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sd.skydip - Function

5.1.1 Determine the opacity from a set of ’skydip’ observations
Description

Determine the opacity from a set of ’skydip’ obervations. This can be any set of observations over a range of elevations, but will ususally be a dedicated (set of) scan(s). Return a list of ’n’ opacities for ’n’ IFs. In case of averagepol being ’False’ a list of ’n*m’ elements where ’m’ is the number of polarisations, e.g. nIF = 3, nPol = 2 [if0pol0, if0pol1, if1pol0, if1pol1, if2pol0, if2pol1]

The opacity is determined by fitting a first order polynomial to:

Tsys(airmass ) = p0 + airmass *p1,

where

airmass =  -----1------
          sin(elevation)

    -p1--
τ = Tsky

Arguments





Inputs

data

File name or scantable or list of them

allowed:

string, string array, scantable, list of scantables

Default:

averagepol

Return opacity values per polarization or average of opacities for the polarizations

allowed:

bool

Default:

True

tsky

The sky temperature

allowed:

float

Default:

300.0

plot

Plot each fit (airmass versus Tsys)

allowed:

bool

Default:

False





Returns
float array

Example

   s=sd.scantable(’skydip.asap’,average=False)  
   sd.skydip(data=s,averagepol=True,plot=True)


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